1. Field of the Invention
The present invention belongs to a technical field of a corrugated fin for composite heat exchangers.
2. Description of the Related Art
A conventional corrugated fin corresponds to required heat release amounts of respective heat exchangers by making a fin width and a number of louver slats different between a condenser side and a radiator side. (For example, refer to Japanese Patent Laid-open No. Hei 10-253276.)
Regarding composite heat exchangers used particularly for motor vehicles, there has been a demand to make thicknesses of a condenser and a radiator, which compose a composite heat exchanger, different according to diversification of size of cabin and diversification of required specification of cooling performance in an engine room. In this case, a corrugated fin should be made to have a different fin width between the condenser side and the radiator side. However, the conventional corrugated fin has such a problem in that, when the fin widths of the corrugated fin integrally formed with the corrugated fin of the composite heat exchanger are made different from each other, an entire corrugated fin bend during a corrugating step due to a difference of residual stresses generated during a louver processing step due to a difference of number of louver slats is formed according to the fin width.